When there is an interruption in the blood supply to a portion of the brain, strokes happen. This interruption is brought on by the three primary types of strokes in distinct ways. Physicians, however, can also categorize strokes based on where they occur.
An emergency in medicine is a stroke. When blood flow to a portion of your brain is disrupted, it occurs. Your brain cells begin to die without blood. Serious symptoms, long-term impairment, and even death may result from this.
Different types of strokes exist. Learn about the three basic types of strokes, their subcategories, and additional classification schemes used by medical professionals by continuing to read.
Table of Contents
Brief stroke of ischemia (TIA)
A TIA, also referred to as a ministroke, is a brief interruption of blood flow to a portion of the brain. The transient nature of the blood clot and TIA symptoms prevents long-term harm.
A TIA may raise your chance of having a stroke in the future and serve as a warning. In order to treat a transient ischemic attack (TIA), preventive measures such as medication and lifestyle modifications are necessary.
Ischemic stroke
An ischemic stroke happens when a thrombus obstructs blood supply to a specific area of the brain. Atherosclerosis, or the accumulation of fatty deposits on the inside of blood vessels, is frequently the cause of blood clots.
The disease process is comparable to a heart attack in that it involves a blood clot obstructing part of the heart’s blood supply.
In contrast to a TIA, the body cannot remove the blood clot that causes an ischemic stroke on its own.
The most prevalent kind of strokes are ischemic strokes. Older U.S. statistics indicates that 87% of strokes are ischemic strokes, however new global data from 2019 indicates that 62.4% of strokes are ischemic strokes.
Types of ischemic stroke: Thrombotic vs. embolic strokes
Based on what causes the blockage, medical professionals might categorize ischemic strokes:
- Thrombotic stroke: When a clot forms in a blood vessel in the brain, it can cause an ischemic stroke. It is the most typical reason why ischemic strokes occur.
- Embolic stroke: An embolic stroke occurs when a blood clot moves from one area of the body to the brain. Most typically, these clots originate in the heart (cardioembolic strokes). The most frequent underlying cause of embolic stroke is a cardiac disease known as atrial fibrillation.
Ischemic stroke types: Lacunar vs. LVO strokes
Medical professionals can also use the size and location of the blood vessels involved to categorize ischemic strokes.
- Lacunar stroke: Small blood arteries located deep within the brain are affected by lacunar strokes. They cause 15% to 25% of all ischemic strokes. Because atherosclerosis can obstruct small blood arteries, lacunar strokes are typically thrombotic rather than embolic. Even though they frequently go undiagnosed and show no symptoms, repeated lacunar strokes can have life-threatening consequences.
- Strokes caused by blockages in the bigger arteries in the brain are known as large vessel occlusion (LVO) strokes. They are more severe than lacunar strokes and account for 24% to 46% of ischemic strokes. Typically, they are embolic.
Hemorrhagic stroke
When a blood vessel in your brain bursts or ruptures, causing blood to leak into the surrounding tissues, it can result in a hemorrhagic stroke. This might be the result of:
- an aneurysm that causes a weak spot in the blood vessel to enlarge and occasionally burst
- an arteriovenous malformation, a birth defect that is usually structural in nature
- extreme hypertension that tears a fragile blood artery in your brain
- Hemorrhagic transformation: bleeding that results from an ischemic stroke
Types of hemorrhagic stroke: ICH vs. SAH
Based on the location of the rupture, specifically whether it takes place in a blood artery inside the brain or on the surface of the brain, medical professionals can categorize hemorrhagic stroke:
Intracerebral hemorrhage (ICH): An ICH occurs when a brain blood vessel bursts. Data from 2019 shows that ICHs cause approximately 75% of hemorrhagic strokes.
A subarachnoid hemorrhage (SAH) occurs when a blood vessel bursts in the subarachnoid space, which is the layer that surrounds the brain.
Types of stroke by hemisphere
The left and right hemispheres make up your brain’s two sides. The left side of your brain governs your right side of the body, while the right side governs your left.
This implies that physical symptoms on the right side of your body may result from a stroke on the left side of your brain, and vice versa.
Lobe cortical strokes
Historically, scientists have divided the cerebral cortex, the brain’s outermost and largest part, into four lobes.
Because each lobe performs a distinct role, strokes in a particular lobe may cause problems or cause particular symptoms. As an illustration:
- Frontal lobe stroke: Your brain’s frontal lobe is in charge of several processes, such as speech, movement, personality, and memory. Since it is the biggest lobe, strokes frequently include it.
- The temporal lobe is located beneath the parietal lobe in a temporal lobe stroke. Speech, hearing, and short-term memory all benefit from it. Here, a stroke can result in a communication disability called aphasia.
- Parietal lobe stroke: Language and sensory information processing depend heavily on the parietal lobe, which is located in the upper middle part of the brain. Aphasia and paresthesia (numbness and tingling) are common side effects of parietal lobe strokes.
- Occipital lobe stroke: Visual processing is handled by the occipital lobe, which is located in the rear of the brain. Vision abnormalities brought on by occcipital strokes include blurriness, visual hallucinations, and cortical blindness.
Region-specific subcortical strokes
A number of areas below the cerebral cortex can also be impacted by strokes. We call these subcortical strokes. As an illustration:
- Basal ganglia stroke: Movement, reward, and cognition are regulated by a network of neurons located deep within the brain called the basal ganglia. Although the results of strokes are comparable to those in other areas, there is a higher chance of bleeding issues during treatment and a higher chance of developing Parkinsonism in the future.
- Brain stem stroke: The brain stem, which is located directly above the spinal cord, is affected by 5% to 13.4% of hemorrhagic strokes and 11% of ischemic strokes. The brain stem controls vital signs, including blood pressure, heart rate, and breathing. According to scientists, brain stem strokes are the most deadly kind of stroke.
- Thalamic stroke: The thalamus, which is located close to the center of the brain, is affected by thalamic strokes, a kind of lacunar stroke. The thalamus is important in memory, consciousness, sleep, and sensation. According to a 2024 study, thalamic stroke patients typically experience a speedy recovery and good long-term prognosis.
- Cerebellar stroke: The cerebellum, which regulates movement and balance, is affected by a cerebellar stroke. Mistaking cerebellar strokes for vertigo can occur occasionally, but delaying treatment can worsen the condition.
Stroke types caused by impacted arteries
Physicians may also mention strokes that involve the following arteries:
- Stroke caused by the middle cerebral artery (MCA): Stroke most frequently occurs in the MCA. It can result in a variety of symptoms because it supplies blood to the parietal, temporal, and frontal lobes. MCA strokes are the most unpredictable type of stroke, with strong treatment being necessary, aside from brain stem strokes.
- Anterior cerebral artery (ACA) strokes are uncommon and usually result in a good prognosis.
The impact is only on the frontal lobe. Urinary incontinence, aphasia, and behavioral abnormalities are examples of distinctive symptoms. - Posterior cerebral artery (PCA) stroke: PCA strokes can induce a wide range of nonspecific symptoms that are inconsistent and difficult to detect. The brain stem and occipital lobe may impact the condition. The results are usually worse when strokes start in the deep areas of the PCA.
What variations exist in stroke treatment?
Numerous variables, such as the kind of stroke and its duration, affect how it is treated. Your chances of making a full recovery increase when healthcare providers diagnose and treat you promptly.
Irrespective of the subtype, ischemic stroke treatment entails removing the blood clot. However, surgery may be necessary, but typically, it requires medication.
Therapy for hemorrhagic strokes aims to lessen the consequences of brain hemorrhage as well as stop brain bleeding. The goal of surgical techniques like coiling or clipping is to stop more bleeding.
The site of the stroke and the ease with which the surgical team can access it frequently determine the surgical alternatives available.
Takeaway
Strokes are classified by doctors as either hemorrhagic (caused by bleeding) or ischemic (caused by a blockage). A transient obstruction that doesn’t result in long-term harm is the cause of a TIA, or ministroke.
However, medical professionals may distinguish between different types of strokes depending on:
- what blocks the flow or bleeds, like embolic or thrombotic strokes
- the area or lobe of the brain, as in the case of occipital lobe or brain stem strokes
- the blood arteries affected, including strokes caused by MCA, ACA, or PCA
This knowledge can help with managing the stroke, anticipating symptoms, and planning for recovery. Discuss with your physician how the sort of stroke you have will affect your course of care and prognosis.